Abstract: The present invention is directed to propellant grains having multiple layers consisting of an outer, slow burning, layer composition and an inner, fast burning, layer with desirable progressivity burn rates. The outer, slow burning, layer comprising a first energetic material, a first plasticizer and a first binder and an inner, fast burning, layer comprising a second energetic material, and the same plasticizer as the outer layer, and a second binder. The compositions in the propellant grain provided herein provides for a burn rate energy differential between the outer, slow burning, layer and inner, fast burning, layer of at least 2.

Abstract: A kinetic energy training cartridge simulates the performance, weight, length, and external geometry of a tactical cartridge. The training cartridge includes a cartridge case and a projectile that is secured to cartridge case by means of a sabot. The sabot includes a rearward extension that encapsulates part of the projectile, to add weight and to increase a length to diameter ratio of the projectile, so as to decrease an intrusion volume of the projectile within the cartridge case. In a preferred embodiment, the length to diameter ratio of the projectile is at least 15.